The title compound [systematic name: 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridinium 2,4,6-trinitrophenolate], C(8)H(12)NO(3)(+)xC(6)H(2)N(3)O(7)(-), is a complex of picric acid with pyridoxine. The asymmetric part of the unit cell contains one pyridoxinium cation and one picrate anion. The aromatic rings of the picrate anion and the pyridoxinium cation are inclined with a dihedral angle of 83.19 (7) degrees . An intramolecular hydrogen bond between OH and a nearby CH(2)OH group is observed in the cation. The hydrophobic layers at y = {1/2} are packed between the hydrophilic layers at y = 0.

In the title compound, C 3 H 8 NO 2 + ÁC 4 H 5 O 6 À , the sarcosinium cation and semi-tartrate anion are held together by a threedimensional network of OÐHÁ Á ÁO, NÐHÁ Á ÁO and CÐHÁ Á ÁO hydrogen bonds. The structure may be described as an inclusion compound with the semi-tartrate anion as the host and the sarcosinium cation as the guest. Comment Single-crystal X-ray investigations on complexes of amino acids with carboxylic acids are interesting in view of their geometrical features and aggregation patterns that might possibly have occurred in prebiotic polymerization (Vijayan, 1988; Prasad & Vijayan, 1993). The present study reports the crystal structure of a complex, (I), of sarcosine with tartaric acid. Sarcosine (N-methylglycine, CH 3 NH 2 + CH 2 COO À) is an-amino acid present in several biologically important compounds and its crystal structure was elucidated in our laboratory (Mostad & Natarajan, 1989).

In the title compound, C6H6NO2+·C2O2F3−, the carboxyl group is twisted from the planar pyridine ring by an angle of 5.2 (6)°. The protonated cations and the anions are linked through N—H...O and O—H...O hydrogen bonds, forming a C21(8) chain motif with two‐dimensional lamellar sheets parallel to (010). These sheets are separated by a distance of 3.092 (4) Å and there are no hydrogen bonds between them. The F atoms are each disordered unequally over two positions.

Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.003 Å R factor = 0.041 wR factor = 0.129 Data-to-parameter ratio = 12.1 For details of how these key indicators were automatically derived from the article, see

In this work, an Acacia concinna filler was blended in a polylactic acid matrix using a single-screw extruder. A composite filament material made from an extruder was used to fabricate polylactic acid/25 wt% A. concinna (PLA/25 wt% AC) composites via a fused deposition modeling (FDM) technique. Composites were fabricated by varying layer thickness, infill density, and printing speed based on Taguchi L9 experimental design. Tensile, flexural, and impact tests were conducted on the printed composite samples as per the ASTM standards. The significance of factors impacting the mechanical properties was determined using analysis of variance. To estimate the strength of PLA/AC composites, mathematical models were developed. In addition, the fractured specimen was examined using scanning electron microscopy to determine the mechanism of fracture. Both the layer height and the infill percentage exhibited a positive influence on strength, which suggests that the layer height or the infill percentage, or both, will increase the material’s strength. The printing speed had a negative influence on the strength, which indicates that the strength decreases as the printing speed increases. The findings suggested that PLA/AC composites could be used to fabricate high-strength, lightweight components using FDM.